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The use of an electrospun polycaprolactone (PCL) nonwoven mat that is coated with a layer of chitosan (CS) containing active ingredient [tea tree oil (TTO)] represents an effective strategy for producing functional dressings. CS-coated porous PCL nonwoven mat (CS3/PCLNM) with various concentrations of active ingredients were produced and investigated. In vitro, active ingredient-containing CS3/PCLNM is effective in inhibiting the formation of nitrite and the growth of Staphylococcus aureus. Both active ingredient TTO and CS have been proven to reach their maximum amount of releases within 24 h of contact with water-based environment. In vivo, full-thickness skin removal (1.2 cm × 1.2 cm) was performed on the back of the C57BL6/J mice in noninfected and infected animal models. Four groups of functional dressings were tested in this work including Tegderm™, PCLNM, CS3/PCLNM, and 100 μL TTO-CS3/PCLNM. After 7 days post-treatment, the bacterial levels were found to be significantly lower in both CS3/PCLNM and 100 μL TTO-CS3/PCLNM-treated groups than in the control group (81.6 ± 18.1% and 93.7 ± 9.57% of reductions in the bacterial load in the pus relative to the control group, respectively). Additionally, based on the histological analyses, the 100 μL TTO-CS3/PCLNM-treated group outperformed all other groups in wound healing.

:catalysts prepared by an electroless deposition method were Cu/SiO 2 investigated and compared with those by an impregnation method. Copper contents varied from 5% to 15% and was used as support. All catalysts were SiO 2 characterized by BET, DSC, SEM and TPR and tested by an n-butanol dehydrogenation reaction for activities and stabilities. BET analysis showed that the catalysts prepared by the two methods present larger average pore size and less surface area than those of the fresh indicating that smaller pores may get SiO 2 , blocked during the course of preparation. This blockage is more severe in the impregnation method. SEM photos showed that the electroless method produces smaller copper crystals than the impregnated method. The reaction activity was found to be in the order of the calcined electroless copper catalyst [ the fresh electroless copper catalyst [ impregnated copper catalyst.1998 Society of ( Chemical Industry

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EDTA/PVDF electrospun nonwoven mats were produced by electrospinning and their heavy metal removal efficiency was evaluated by chelating filtration using electropolishing electrolyte as the processing target. Scanning electron microscopic (SEM) images revealed that the electrospun nonwoven mats comprised randomly oriented PVDF fibers (avg. diameter=476±145 nm) whose surfaces were decorated with EDTA particles. Attenuated total reflectance infrared (ATR-IR) and X-ray photoelectron spectroscopy (XPS) indicated that the surface of the PVDF fibers exhibited tertiary amino and carboxylic acid groups, which were responsible for the removal of heavy metal ions. Metal-chelating filtration test showed that the produced EDTA/PVDF electrospun nonwoven mats removed 19 %, 18 %, and 60 % of the Fe, Cr, and Ni in the electropolishing electrolyte within 30 running cycles of metal-chelating filtration. The adsorption process is fitted well to the Freundlich isotherm model probably owing to that Freundlich isotherm model is the most important model for multisite adsorption of rough surfaces. This study provides a novel extraction material and procedure for the removal of soluble, sparingly soluble and insoluble heavy metal ions or particles from chemical sewage, such as that which drains away from electroplating or electropolishing plants.